The Delft Sand, Clay & Rock Cutting Model, 2019a

Dry Sand Cutting.
Horizontal Cutting Force Coefficient λ HD vs. Blade Angle α
40
Horizontal Cutting Force Coefficient λ HD (-)
38
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
φ=25°
φ=30°
φ=35°
φ=40°
φ=45°
φ=50°
0
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Blade Angle α (Degrees)
© S.A.M.
Figure 5-11: The horizontal cutting force coefficient λHD as a function of
the blade angle α for hb/hi=2.
Vertical Cutting Force Coefficient λ VD vs. Blade Angle α
15.0
12.5
φ=25°
Vertical Cutting Force Coefficient λ VD (-)
10.0
7.5
5.0
2.5
0.0
-2.5
-5.0
-7.5
-10.0
φ=30°
φ=35°
φ=40°
φ=45°
-12.5
φ=50°
-15.0
15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90
Blade Angle α (Degrees)
© S.A.M.
Figure 5-12: The vertical cutting force coefficient λVD as a function of
the blade angle α for hb/hi=2.
The contribution of the inertial effect only depends on the dimensionless inertial effect parameter λi and not on the
cutting velocity or layer thickness individually. The dimensionless inertial effect parameter λi in fact is a Froude
number of the cutting process. Figure 5-15, Figure 5-16 and Figure 5-17 show the shear angle and both horizontal
and vertical cutting force coefficients at very high values of the dimensionless inertial effect parameter λi (λi=250).
The shear angles are considerably smaller than in the case where inertial forces can be neglected. Also in the case
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